Kwon et al recently demonstrated that Kim-1 expression predicts renal outcomes in IgA nephropathy [27], whilst elevated Kim-1 levels have also been reported in DN [28] and decreasing levels associated with regression of microalbuminuria in type 1 diabetes, suggesting that tubular dysfunction is a critical component of the early course of DN [29]. This evidence concerns the gene HAVCR1 and type 1 diabetes mellitus.